223 research outputs found
Characteristics and Fertility Status of Soils and Minesoils in Selected Areas of Usibelli Coal Mine, Healy, Alaska
Alaska has been proven to contain not only bountiful oil and gas reserves. but also vast coal fields occurring from the southcentral coastline to the Interior and the Arctic zone to the north. Because of concerns for stable sources of energy, particularly by the energy-short, industrial nations of the Orient, more exploration and stripmining for coal can be expected in the near future. Therefore, it is important to know the consequences of large-area soil disturbances tn the subarctic and bow the effects of man's reclamation efforts and natural processes combine in reestablishing vegetative community. The culmination or synthesis of these processes is soil development and is of great importance in successful stripmine reclamation.
The Usibelli Coal Mine Company in the Healy coal field, located in Interior Alaska. commenced stripmining in 1943. Its operation has been continuous, moving from area to area, for the last 40 years. Stripmining requires the excavation of overburden and subsequent redeposition, therefore the Healy operation has exposed minespoils from different strata on various topography. In 1972, the Usibelli Coal Mine company initiated a reclamation program and, over the ensuing l0 years, has seeded and fertilized over 2000 acres. Nevertheless, there remain barren areas and areas undergoing natural revegetation. Additionally, experimental trials in seeding and fertilization were started in 1980. Large areas of intact native plant communities adjoin the mined areas. The company property provides opportunities to study the processes of soil formation under different sets of conditions.
The objectives of this study were to (1) characterize the soils on the mine lease area for baseline data, (2) to characterize the mine soils with various history, (3) to study the process of soil formation under different sets of conditions, and (4) to evaluate the nutrient levels of both soil and minesoils to form a basis for establishing soil-handling requirements to promote reclamation practices.This study was supported by funds from the U.S. Department of Energy (AM06-76RL02229) and the U.S. Department of Agriculture Hatch project. Our appreciation to Drs. W.M. Mitchell. G.A. Mitchell. and F. Wooding of the Agricultural and Forestry Experiment Station. and Mr. J.P. Moore of USDA Son Conservation Service for reviewing the manuscript and offering many useful suggestions.
Our appreciation also to Dr. Milton A. Wiltse of Division of Geological and Geophysical Surveys. Department of Natural Resources for access to the X-ray diffractometer and technical advice. Special thanks to the Usibelli Coal Mine Inc. for logistic and technical assistance tn carrying out this study
Foreign Illegal, Unreported, and Unregulated Fishing in Somali Waters Perpetuates Conflict
Somali waters have high fisheries production potential, but the sustainability of those fisheries is compromised by the presence of foreign fishing vessels, many of them fishing illegally. The Somali domestic fishing sector is small and relatively nascent, but foreign vessels have fished in Somali waters for at least seven decades. Some foreign vessels and their crew have been a direct, physical threat to Somali artisanal fishers. Many foreign vessels directly compete for fish, reducing fish populations and destroying marine habitat through bottom trawling. In this paper, we reconstruct foreign catch in Somali waters from 1981–2014 and classify the health of seventeen commercial fish stocks. Foreign fishing has increased more than twenty-fold since 1981, and the most rapid increase occurred during the 1990s after the collapse of the Federal government and ensuing civil war
The construction and validation of a short form of the developmental, diagnostic and dimensional interview
We aimed to construct and validate a shortened form of the developmental, diagnostic and dimensional interview (3Di), a parent report interview for assessing and diagnosing autistic spectrum disorders (ASDs). Data from 879 children and young people were used. In half of the sample (n = 440) reliability analysis was used to identify 3Di items that best measured each dimension of the autism triad. This informed the construction of a shortened (53 item) 3Di, which was then validated on subjects not used in the reliability analysis (n = 439). This involved comparison with scores from the original 3Di algorithm and, in a subsample (n = 29), with the autism diagnostic interview-revised (ADI-R). Agreement of the new shortened 3Di with the 3Di’s original algorithm was excellent in both dimensional and categorical terms. Agreement on caseness (27 out of 29) with the ADI-R was also strong. The new 3Di short version is less than half as long as the original version and outputs very similar scores. It will be useful to clinicians and researchers for obtaining a dimensional autism assessment in less than 45 minutes
Bacteroides abundance drives birth mode dependent infant gut microbiota developmental trajectories
Background and aimsBirth mode and other early life factors affect a newborn's microbial colonization with potential long-term health effects. Individual variations in early life gut microbiota development, especially their effects on the functional repertoire of microbiota, are still poorly characterized. This study aims to provide new insights into the gut microbiome developmental trajectories during the first year of life. MethodsOur study comprised 78 term infants sampled at 3 weeks, 3 months, 6 months, and 12 months (n = 280 total samples), and their mothers were sampled in late pregnancy (n = 50). Fecal DNA was subjected to shotgun metagenomic sequencing. Infant samples were studied for taxonomic and functional maturation, and maternal microbiota was used as a reference. Hierarchical clustering on taxonomic profiles was used to identify the main microbiota developmental trajectories in the infants, and their associations with perinatal and postnatal factors were assessed. ResultsIn line with previous studies, infant microbiota composition showed increased alpha diversity and decreased beta diversity by age, converging toward an adult-like profile. However, we did not observe an increase in functional alpha diversity, which was stable and comparable with the mother samples throughout all the sampling points. Using a de novo clustering approach, two main infant microbiota clusters driven by Bacteroidaceae and Clostridiaceae emerged at each time point. The clusters were associated with birth mode and their functions differed mainly in terms of biosynthetic and carbohydrate degradation pathways, some of which consistently differed between the clusters for all the time points. The longitudinal analysis indicated three main microbiota developmental trajectories, with the majority of the infants retaining their characteristic cluster until 1 year. As many as 40% of vaginally delivered infants were grouped with infants delivered by C-section due to their clear and persistent depletion in Bacteroides. Intrapartum antibiotics, any perinatal or postnatal factors, maternal microbiota composition, or other maternal factors did not explain the depletion in Bacteroides in the subset of vaginally born infants. ConclusionOur study provides an enhanced understanding of the compositional and functional early life gut microbiota trajectories, opening avenues for investigating elusive causes that influence non-typical microbiota development.Peer reviewe
Ecotoxicity evaluation using the avoidance response of the oribatid mite Oppia nitens (Acari: Oribatida) in bioplastics, microplastics, and contaminated Superfund field sites
Bioplastics are considered sustainable alternatives to conventional microplastics which are recognized as a threat to terrestrial ecosystems. However, little is known about the potential ecotoxicological effects of bioplastics on soil fauna and ecosystems. The present study assessed the toxicity of microplastics [Polystyrene (PS), Polyethylene (PE)] and bioplastics [Polyvinyl alcohol (PVA), Sodium polyacrylate (NaPa) on a key soil fauna Oppia nitens, a soil oribatid mite, and investigated the ecological relevance of O. nitens avoidance response as a valuable tool for the risk assessment of contaminated soils such as the Superfund sites. Findings showed that the mites’ net response indicated avoidance behavior such that in most cases as concentrations of micro- and bioplastics increased, so did the avoidance responses. The avoidance EC50 endpoints showed PS \u3c PE \u3c PVA \u3c NaPa, indicating higher deleterious effects of microplastics. High toxicity of PS in soils to O. nitens at EC50 of 165 (±25) mg/kg compared to bioplastics and other known contaminants poses an enormous threat to soil. For bioplastics in this study, there were no significant avoidances at concentrations up to 16,200 mg/kg compared to PS and PE which showed avoidance responses at 300 and 9000 mg/kg respectively, implying that bioplastics might be relatively safer to soil mites compared to conventional microplastics. Also, results indicated that long-term heavy metal pollution such as in contaminated Superfund sites decreased microbial biomass; a useful bioindicator of soil pollution. Furthermore, O. nitens avoidance of heavy metals contaminated sites demonstrated the ecological relevance of avoidance response test when assessing the habitat integrity of contaminated soil. The present study further supports the inclusion of the oribatid mite, O. nitens in the ecological risk assessment of contaminants in soil
Bridge study protocol : an international, observational cohort study on the transition of healthcare for adolescents with chronic conditions
Introduction More than 10% of adolescents live with a chronic disease or disability that requires regular medical follow-up as they mature into adulthood. During the first 2 years after adolescents with chronic conditions are transferred to adult hospitals, non-adherence rates approach 70% and emergency visits and hospitalisation rates significantly increase. The purpose of the Bridge study is to prospectively examine associations of transition readiness and care experiences with transition success: young patients' health, health-related quality of life (HRQoL) and adherence to medical appointments as well as costs of care. In addition, we will track patients' growing independence and educational and employment pathways during the transition process. Methods and analysis Bridge is an international, prospective, observational cohort study. Study participants are adolescents with a chronic health condition or disability and their parents/guardians who attended the New Children's Hospital in Helsinki, Finland, or the Royal Children's Hospital (RCH) in Melbourne, Australia. Baseline assessment took place approximately 6 months prior to the transfer of care and follow-up data will be collected 1 year and 2 years after the transfer of care. Data will be collected from patients' hospital records and from questionnaires completed by the patient and their parent/guardian at each time point. The primary outcomes of this study are adherence to medical appointments, clinical health status and HRQoL and costs of care. Secondary outcome measures are educational and employment outcomes. Ethics and dissemination The Ethics Committee for Women's and Children's Health and Psychiatry at the Helsinki University Hospital (HUS/1547/2017) and the RCH Human Research Ethics Committee (38035) have approved the Bridge study protocol. Results will be published in international peer-reviewed journals and summaries will be provided to the funders of the study as well as patients and their parents/guardians.Peer reviewe
An extended catalog of integrated prophages in the infant and adult fecal microbiome shows high prevalence of lysogeny
Background and aimsThe acquisition and gradual maturation of gut microbial communities during early childhood is central to an individual’s healthy development. Bacteriophages have the potential to shape the gut bacterial communities. However, the complex ecological interactions between phages and their bacterial host are still poorly characterized. In this study, we investigated the abundance and diversity of integrated prophages in infant and adult gut bacteria by detecting integrated prophages in metagenome assembled genomes (MAGs) of commensal bacteria.MethodsOur study included 88 infants sampled at 3 weeks, 3 months, 6 months, and 12 months (n = 323 total samples), and their parents around delivery time (n = 138 total samples). Fecal DNA was extracted and characterized by using shotgun metagenomic sequencing, and a collection of prokaryotic MAGs was generated. The MAG collection was screened for the presence of integrated bacteriophage sequences, allowing their taxonomic and functional characterization.ResultsA large collection of 6,186 MAGs from infant and adult gut microbiota was obtained and screened for integrated prophages, allowing the identification of 7,165 prophage sequences longer than 10 kb. Strikingly, more than 70% of the near-complete MAGs were identified as lysogens. The prevalence of prophages in MAGs varied across bacterial families, with a lower prevalence observed among Coriobacteriaceae, Eggerthellaceae, Veillonellaceae and Burkholderiaceae, while a very high prevalence of lysogen MAGs were observed in Oscillospiraceae, Enterococcaceae, and Enterobacteriaceae. Interestingly for several bacterial families such as Bifidobacteriaceae and Bacteroidaceae, the prevalence of prophages in MAGs was higher in early infant time point (3 weeks and 3 months) than in later sampling points (6 and 12 months) and in adults. The prophage sequences were clustered into 5,616 species-like vOTUs, 77% of which were novel. Finally, we explored the functional repertoire of the potential auxiliary metabolic genes carried by these prophages, encoding functions involved in carbohydrate metabolism and degradation, amino acid metabolism and carbon metabolism.ConclusionOur study provides an enhanced understanding of the diversity and prevalence of lysogens in infant and adult gut microbiota and suggests a complex interplay between prophages and their bacterial hosts
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